lib/tty/tty.c

lib/tty/tty.c
/* */
This source file includes following definitions.
sigintr_handler
tty_check_term
tty_start_interrupt_key
tty_enable_interrupt_key
tty_disable_interrupt_key
tty_got_interrupt
tty_got_winch
tty_flush_winch
tty_print_one_hline
tty_print_one_vline
tty_draw_box
tty_draw_box_shadow
mc_tty_normalize_from_utf8
tty_resize
tty_clear_screen
tty_init_xterm_support
   1 /*
   2    Interface to the terminal controlling library.
   3 
   4    Copyright (C) 2005-2025
   5    Free Software Foundation, Inc.
   6 
   7    Written by:
   8    Roland Illig <roland.illig@gmx.de>, 2005.
   9    Andrew Borodin <aborodin@vmail.ru>, 2009.
  10 
  11    This file is part of the Midnight Commander.
  12 
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17 
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22 
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <https://www.gnu.org/licenses/>.
  25  */
  26 
  27 /** \file tty.c
  28  *  \brief Source: %interface to the terminal controlling library
  29  */
  30 
  31 #include <config.h>
  32 
  33 #include <errno.h>
  34 #include <signal.h>
  35 #include <stdarg.h>
  36 #include <stdlib.h>
  37 #include <string.h>  // memset()
  38 
  39 #ifdef HAVE_SYS_SELECT_H
  40 #    include <sys/select.h>
  41 #else
  42 #    include <sys/time.h>
  43 #    include <sys/types.h>
  44 #endif
  45 #include <unistd.h>  // exit()
  46 
  47 #ifdef HAVE_SYS_IOCTL_H
  48 #    include <sys/ioctl.h>
  49 #endif
  50 
  51 /* In some systems (like Solaris 11.4 SPARC), TIOCSWINSZ is defined in termios.h */
  52 #include <termios.h>
  53 
  54 #include "lib/global.h"
  55 #include "lib/strutil.h"
  56 #include "lib/util.h"
  57 
  58 #include "tty.h"
  59 #include "tty-internal.h"
  60 #include "color.h"  // tty_set_normal_attrs()
  61 #include "mouse.h"  // use_mouse_p
  62 #include "win.h"
  63 
  64 /*** global variables ****************************************************************************/
  65 
  66 int mc_tty_frm[MC_TTY_FRM_MAX];
  67 
  68 /*** file scope macro definitions ****************************************************************/
  69 
  70 /*** file scope type declarations ****************************************************************/
  71 
  72 /*** forward declarations (file scope functions) *************************************************/
  73 
  74 /*** file scope variables ************************************************************************/
  75 
  76 static SIG_ATOMIC_VOLATILE_T got_interrupt = 0;
  77 
  78 /* --------------------------------------------------------------------------------------------- */
  79 /*** file scope functions ************************************************************************/
  80 /* --------------------------------------------------------------------------------------------- */
  81 
  82 static void
  83 sigintr_handler (int signo)
     /*   */
  84 {
  85     (void) &signo;
  86     got_interrupt = 1;
  87 }
  88 
  89 /* --------------------------------------------------------------------------------------------- */
  90 /*** public functions ****************************************************************************/
  91 /* --------------------------------------------------------------------------------------------- */
  92 
  93 /**
  94  * Check terminal type. If $TERM is not set or value is empty, mc finishes with EXIT_FAILURE.
  95  *
  96  * @param force_xterm Set forced the XTerm type
  97  *
  98  * @return true if @param force_xterm is true or value of $TERM is one of following:
  99  *         term*
 100  *         konsole*
 101  *         rxvt*
 102  *         Eterm
 103  *         dtterm
 104  *         alacritty*
 105  *         foot*
 106  *         screen*
 107  *         tmux*
 108  *         contour*
 109  */
 110 gboolean
 111 tty_check_term (gboolean force_xterm)
     /*   */
 112 {
 113     const char *termvalue;
 114 
 115     termvalue = getenv ("TERM");
 116     if (termvalue == NULL || *termvalue == '\0')
 117     {
 118         fputs (_ ("The TERM environment variable is unset!\n"), stderr);
 119         exit (EXIT_FAILURE);
 120     }
 121 
 122     return force_xterm || strncmp (termvalue, "xterm", 5) == 0
 123         || strncmp (termvalue, "konsole", 7) == 0 || strncmp (termvalue, "rxvt", 4) == 0
 124         || strcmp (termvalue, "Eterm") == 0 || strcmp (termvalue, "dtterm") == 0
 125         || strncmp (termvalue, "alacritty", 9) == 0 || strncmp (termvalue, "foot", 4) == 0
 126         || strncmp (termvalue, "screen", 6) == 0 || strncmp (termvalue, "tmux", 4) == 0
 127         || strncmp (termvalue, "contour", 7) == 0;
 128 }
 129 
 130 /* --------------------------------------------------------------------------------------------- */
 131 
 132 extern void
 133 tty_start_interrupt_key (void)
     /*   */
 134 {
 135     struct sigaction act;
 136 
 137     memset (&act, 0, sizeof (act));
 138     act.sa_handler = sigintr_handler;
 139     sigemptyset (&act.sa_mask);
 140 #ifdef SA_RESTART
 141     act.sa_flags = SA_RESTART;
 142 #endif
 143     my_sigaction (SIGINT, &act, NULL);
 144 }
 145 
 146 /* --------------------------------------------------------------------------------------------- */
 147 
 148 extern void
 149 tty_enable_interrupt_key (void)
     /*   */
 150 {
 151     struct sigaction act;
 152 
 153     memset (&act, 0, sizeof (act));
 154     act.sa_handler = sigintr_handler;
 155     sigemptyset (&act.sa_mask);
 156     my_sigaction (SIGINT, &act, NULL);
 157     got_interrupt = 0;
 158 }
 159 
 160 /* --------------------------------------------------------------------------------------------- */
 161 
 162 extern void
 163 tty_disable_interrupt_key (void)
     /*   */
 164 {
 165     struct sigaction act;
 166 
 167     memset (&act, 0, sizeof (act));
 168     act.sa_handler = SIG_IGN;
 169     sigemptyset (&act.sa_mask);
 170     my_sigaction (SIGINT, &act, NULL);
 171 }
 172 
 173 /* --------------------------------------------------------------------------------------------- */
 174 
 175 extern gboolean
 176 tty_got_interrupt (void)
     /*   */
 177 {
 178     gboolean rv;
 179 
 180     rv = (got_interrupt != 0);
 181     got_interrupt = 0;
 182     return rv;
 183 }
 184 
 185 /* --------------------------------------------------------------------------------------------- */
 186 
 187 gboolean
 188 tty_got_winch (void)
     /*   */
 189 {
 190     fd_set fdset;
 191     // instant timeout
 192     struct timeval timeout = { .tv_sec = 0, .tv_usec = 0 };
 193     int ok;
 194 
 195     FD_ZERO (&fdset);
 196     FD_SET (sigwinch_pipe[0], &fdset);
 197 
 198     while ((ok = select (sigwinch_pipe[0] + 1, &fdset, NULL, NULL, &timeout)) < 0)
 199         if (errno != EINTR)
 200         {
 201             perror (_ ("Cannot check SIGWINCH pipe"));
 202             exit (EXIT_FAILURE);
 203         }
 204 
 205     return (ok != 0 && FD_ISSET (sigwinch_pipe[0], &fdset));
 206 }
 207 
 208 /* --------------------------------------------------------------------------------------------- */
 209 
 210 gboolean
 211 tty_flush_winch (void)
     /*   */
 212 {
 213     ssize_t n;
 214     gboolean ret = FALSE;
 215 
 216     // merge all SIGWINCH events raised to this moment
 217     do
 218     {
 219         char x[16];
 220 
 221         // read multiple events at a time
 222         n = read (sigwinch_pipe[0], &x, sizeof (x));
 223 
 224         // at least one SIGWINCH came
 225         if (n > 0)
 226             ret = TRUE;
 227     }
 228     while (n > 0 || (n == -1 && errno == EINTR));
 229 
 230     return ret;
 231 }
 232 
 233 /* --------------------------------------------------------------------------------------------- */
 234 
 235 void
 236 tty_print_one_hline (gboolean single)
     /*   */
 237 {
 238     tty_print_alt_char (ACS_HLINE, single);
 239 }
 240 
 241 /* --------------------------------------------------------------------------------------------- */
 242 
 243 void
 244 tty_print_one_vline (gboolean single)
     /*   */
 245 {
 246     tty_print_alt_char (ACS_VLINE, single);
 247 }
 248 
 249 /* --------------------------------------------------------------------------------------------- */
 250 
 251 void
 252 tty_draw_box (int y, int x, int ys, int xs, gboolean single)
     /*   */
 253 {
 254     int y2, x2;
 255 
 256     if (ys <= 0 || xs <= 0)
 257         return;
 258 
 259     ys--;
 260     xs--;
 261 
 262     y2 = y + ys;
 263     x2 = x + xs;
 264 
 265     tty_draw_vline (y, x, mc_tty_frm[single ? MC_TTY_FRM_VERT : MC_TTY_FRM_DVERT], ys);
 266     tty_draw_vline (y, x2, mc_tty_frm[single ? MC_TTY_FRM_VERT : MC_TTY_FRM_DVERT], ys);
 267     tty_draw_hline (y, x, mc_tty_frm[single ? MC_TTY_FRM_HORIZ : MC_TTY_FRM_DHORIZ], xs);
 268     tty_draw_hline (y2, x, mc_tty_frm[single ? MC_TTY_FRM_HORIZ : MC_TTY_FRM_DHORIZ], xs);
 269     tty_gotoyx (y, x);
 270     tty_print_alt_char (ACS_ULCORNER, single);
 271     tty_gotoyx (y2, x);
 272     tty_print_alt_char (ACS_LLCORNER, single);
 273     tty_gotoyx (y, x2);
 274     tty_print_alt_char (ACS_URCORNER, single);
 275     tty_gotoyx (y2, x2);
 276     tty_print_alt_char (ACS_LRCORNER, single);
 277 }
 278 
 279 /* --------------------------------------------------------------------------------------------- */
 280 
 281 void
 282 tty_draw_box_shadow (int y, int x, int rows, int cols, int shadow_color)
     /*   */
 283 {
 284     // draw right shadow
 285     tty_colorize_area (y + 1, x + cols, rows - 1, 2, shadow_color);
 286     // draw bottom shadow
 287     tty_colorize_area (y + rows, x + 2, 1, cols, shadow_color);
 288 }
 289 
 290 /* --------------------------------------------------------------------------------------------- */
 291 
 292 char *
 293 mc_tty_normalize_from_utf8 (const char *str)
     /*   */
 294 {
 295     GIConv conv;
 296     GString *buffer;
 297     const char *_system_codepage = str_detect_termencoding ();
 298 
 299     if (str_isutf8 (_system_codepage))
 300         return g_strdup (str);
 301 
 302     conv = g_iconv_open (_system_codepage, "UTF-8");
 303     if (conv == INVALID_CONV)
 304         return g_strdup (str);
 305 
 306     buffer = g_string_new ("");
 307 
 308     if (str_convert (conv, str, buffer) == ESTR_FAILURE)
 309     {
 310         g_string_free (buffer, TRUE);
 311         str_close_conv (conv);
 312         return g_strdup (str);
 313     }
 314     str_close_conv (conv);
 315 
 316     return g_string_free (buffer, FALSE);
 317 }
 318 
 319 /* --------------------------------------------------------------------------------------------- */
 320 
 321 /** Resize given terminal using TIOCSWINSZ, return ioctl() result */
 322 int
 323 tty_resize (int fd)
     /*   */
 324 {
 325 #if defined TIOCSWINSZ
 326     struct winsize tty_size;
 327 
 328     tty_size.ws_row = LINES;
 329     tty_size.ws_col = COLS;
 330     tty_size.ws_xpixel = tty_size.ws_ypixel = 0;
 331 
 332     return ioctl (fd, TIOCSWINSZ, &tty_size);
 333 #else
 334     return 0;
 335 #endif
 336 }
 337 
 338 /* --------------------------------------------------------------------------------------------- */
 339 
 340 /** Clear screen */
 341 void
 342 tty_clear_screen (void)
     /*   */
 343 {
 344     tty_set_normal_attrs ();
 345     tty_fill_region (0, 0, LINES, COLS, ' ');
 346     tty_refresh ();
 347 }
 348 
 349 /* --------------------------------------------------------------------------------------------- */
 350 
 351 void
 352 tty_init_xterm_support (gboolean is_xterm)
     /*   */
 353 {
 354     const char *termvalue;
 355 
 356     termvalue = getenv ("TERM");
 357 
 358     // Check mouse and ca capabilities
 359     /* terminfo/termcap structures have been already initialized,
 360        in slang_init() or/and init_curses()  */
 361     // Check terminfo at first, then check termcap
 362     xmouse_seq = tty_tgetstr ("kmous");
 363     if (xmouse_seq == NULL)
 364         xmouse_seq = tty_tgetstr ("Km");
 365     smcup = tty_tgetstr ("smcup");
 366     if (smcup == NULL)
 367         smcup = tty_tgetstr ("ti");
 368     rmcup = tty_tgetstr ("rmcup");
 369     if (rmcup == NULL)
 370         rmcup = tty_tgetstr ("te");
 371 
 372     if (strcmp (termvalue, "cygwin") == 0)
 373     {
 374         is_xterm = TRUE;
 375         use_mouse_p = MOUSE_DISABLED;
 376     }
 377 
 378     if (is_xterm)
 379     {
 380         // Default to the standard xterm sequence
 381         if (xmouse_seq == NULL)
 382             xmouse_seq = ESC_STR "[M";
 383 
 384         // Enable mouse unless explicitly disabled by --nomouse
 385         if (use_mouse_p != MOUSE_DISABLED)
 386         {
 387             if (mc_global.tty.old_mouse)
 388                 use_mouse_p = MOUSE_XTERM_NORMAL_TRACKING;
 389             else
 390             {
 391                 // FIXME: this dirty hack to set supported type of tracking the mouse
 392                 const char *color_term = getenv ("COLORTERM");
 393                 if (strncmp (termvalue, "rxvt", 4) == 0
 394                     || (color_term != NULL && strncmp (color_term, "rxvt", 4) == 0)
 395                     || strcmp (termvalue, "Eterm") == 0)
 396                     use_mouse_p = MOUSE_XTERM_NORMAL_TRACKING;
 397                 else
 398                     use_mouse_p = MOUSE_XTERM_BUTTON_EVENT_TRACKING;
 399             }
 400         }
 401     }
 402 
 403     /* There's only one termcap entry "kmous", typically containing "\E[M" or "\E[<".
 404      * We need the former in xmouse_seq, the latter in xmouse_extended_seq.
 405      * See tickets 2956, 3954, and 4063 for details. */
 406     if (xmouse_seq != NULL)
 407     {
 408         if (strcmp (xmouse_seq, ESC_STR "[<") == 0)
 409             xmouse_seq = ESC_STR "[M";
 410 
 411         xmouse_extended_seq = ESC_STR "[<";
 412     }
 413 }
 414 
 415 /* --------------------------------------------------------------------------------------------- */
/* */
root/lib/tty/tty.c

DEFINITIONS
